The European Medicines Agency has accelerated the approval process for a Covid-19 vaccine developed by Germany’s BioNTech and US pharma group Pfizer, to allow for the rapid authorisation of the shot as soon as safety data from its trial allows.

The decision by the EU regulator was based on preliminary results from the companies’ early clinical trials, which showed the vaccine triggers an immune response in adults, the regulator and the companies said on Tuesday.

The Pfizer/BioNTech shot is the second Covid-19 vaccine to be approved for the EMA’s accelerated process, which involves conducting “rolling reviews” of the trial data while the trial is ongoing. Last week, the agency confirmed that it had started that process with the vaccine developed by AstraZeneca and the University of Oxford.